one who was once cold-hearted, but becomes a nice person after the introduction of something new in his or her life.
(from the popular children's christmas claymation movie, Santa Claus is Coming to Town)
Fool #1: "Wow Patty is a Winter Warlock!!"
Fool #2: "Yeah, well Andy gave her the choo choo train and now her icy cold heart is melting."
Patty: "I love you fools."